rulimine/limine-install.c

84 lines
2.2 KiB
C

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>
#include <stddef.h>
#include <inttypes.h>
int main(int argc, char *argv[]) {
FILE *bootloader_file, *device;
uint8_t *bootloader_img;
uint8_t orig_mbr[70], timestamp[6];
uint32_t stage2_sect, sect_size;
if (argc < 3) {
printf("Usage: %s <bootloader image> <device> [<stage2 start sector> <sector size>]\n", argv[0]);
return 1;
}
bootloader_file = fopen(argv[1], "rb");
if (bootloader_file == NULL) {
perror("Error: ");
return 1;
}
// The bootloader image is 64 sectors (32k)
bootloader_img = malloc(64 * 512);
if (bootloader_img == NULL) {
perror("Error: ");
fclose(bootloader_file);
return 1;
}
// Load in bootloader image
fseek(bootloader_file, 0, SEEK_SET);
fread(bootloader_img, 64, 512, bootloader_file);
fclose(bootloader_file);
device = fopen(argv[2], "r+b");
if (device == NULL) {
perror("Error: ");
free(bootloader_img);
return 1;
}
stage2_sect = 0;
sect_size = 512;
if (argc >= 4)
sscanf(argv[3], "%" SCNu32, &stage2_sect);
if (argc >= 5)
sscanf(argv[4], "%" SCNu32, &sect_size);
// Save original timestamp
fseek(device, 218, SEEK_SET);
fread(timestamp, 1, 6, device);
// Save the original partition table of the device
fseek(device, 440, SEEK_SET);
fread(orig_mbr, 1, 70, device);
// Write the bootsector from the bootloader to the device
fseek(device, 0, SEEK_SET);
fwrite(&bootloader_img[0], 1, 512, device);
// Write the rest of stage 2 to the device
fseek(device, stage2_sect * sect_size, SEEK_SET);
fwrite(&bootloader_img[0], 64, 512, device);
// Hardcode in the bootsector the location of stage 2
fseek(device, 0x1b0, SEEK_SET);
fwrite(&stage2_sect, 1, sizeof(uint32_t), device);
// Write back timestamp
fseek(device, 218, SEEK_SET);
fwrite(timestamp, 1, 6, device);
// Write back the saved partition table to the device
fseek(device, 440, SEEK_SET);
fwrite(orig_mbr, 1, 70, device);
fclose(device);
free(bootloader_img);
return 0;
}